1/*
2 * Copyright 2007 the original author or authors.
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16package org.mockftpserver.stub.command;
17
18import org.mockftpserver.core.command.AbstractCommandHandler;
19import org.mockftpserver.core.command.Command;
20import org.mockftpserver.core.command.CommandHandler;
21import org.mockftpserver.core.command.InvocationRecord;
22import org.mockftpserver.core.command.ReplyCodes;
23import org.mockftpserver.core.session.Session;
24import org.mockftpserver.core.util.AssertFailedException;
25
26/**
27 * Abstract superclass for CommandHandlers that read from or write to the data connection.
28 * <p>
29 * Return two replies on the control connection: by default a reply code of 150 before the
30 * data transfer across the data connection and another reply of 226 after the data transfer
31 * is complete.
32 * <p>
33 * This class implements the <i>Template Method</i> pattern. Subclasses must implement the abstract
34 * {@link #processData()} method to perform read or writes across the data connection.
35 * <p>
36 * Subclasses can optionally override the {@link #beforeProcessData(Command, Session, InvocationRecord)}
37 * method for logic before the data transfer or the {@link #afterProcessData(Command, Session, InvocationRecord)}
38 * method for logic after the data transfer.
39 * <p>
40 * Subclasses can optionally override the reply code and/or text for the initial reply (before
41 * the data transfer across the data connection) by calling {@link #setPreliminaryReplyCode(int)},
42 * {@link #setPreliminaryReplyMessageKey(String)} and/or {@link #setPreliminaryReplyText(String)}
43 * methods.
44 * <p>
45 * Subclasses can optionally override the reply code and/or text for the final reply (after the
46 * the data transfer is complete) by calling {@link #setFinalReplyCode(int)},
47 * {@link #setFinalReplyMessageKey(String)} and/or {@link #setFinalReplyText(String)} methods.
48 *
49 * @version $Revision$ - $Date$
50 *
51 * @author Chris Mair
52 */
53public abstract class AbstractStubDataCommandHandler extends AbstractCommandHandler implements CommandHandler {
54
55    // The completion reply code sent before the data transfer
56    protected int preliminaryReplyCode = 0;
57
58    // The text for the preliminary reply. If null, use the default message associated with the reply code.
59    // If not null, this value overrides the preliminaryReplyMessageKey - i.e., this text is used instead of
60    // a localized message.
61    protected String preliminaryReplyText = null;
62
63    // The message key for the preliminary reply text. If null, use the default message associated with
64    // the reply code.
65    protected String preliminaryReplyMessageKey = null;
66
67    // The completion reply code sent after data transfer
68    protected int finalReplyCode = 0;
69
70    // The text for the completion reply. If null, use the default message associated with the reply code.
71    // If not null, this value overrides the finalReplyMessageKey - i.e., this text is used instead of
72    // a localized message.
73    protected String finalReplyText = null;
74
75    // The message key for the completion reply text. If null, use the default message associated with the reply code
76    protected String finalReplyMessageKey = null;
77
78    /**
79     * Constructor. Initialize the preliminary and final reply code.
80     */
81    protected AbstractStubDataCommandHandler() {
82        setPreliminaryReplyCode(ReplyCodes.SEND_DATA_INITIAL_OK);
83        setFinalReplyCode(ReplyCodes.SEND_DATA_FINAL_OK);
84    }
85
86    /**
87     * Handle the command. Perform the following steps:
88     * <ol>
89     * <li>Invoke the {@link #beforeProcessData()} method</li>
90     * <li>Open the data connection</li>
91     * <li>Send an preliminary reply, default reply code 150</li>
92     * <li>Invoke the {@link #processData()} method</li>
93     * <li>Close the data connection</li>
94     * <li>Send the final reply, default reply code 226</li>
95     * <li>Invoke the {@link #afterProcessData()} method</li>
96     * </ol>
97     *
98     * @see org.mockftpserver.core.command.CommandHandler#handleCommand(Command, Session, InvocationRecord)
99     */
100    public final void handleCommand(Command command, Session session, InvocationRecord invocationRecord) throws Exception {
101
102        beforeProcessData(command, session, invocationRecord);
103
104        sendPreliminaryReply(session);
105        session.openDataConnection();
106        processData(command, session, invocationRecord);
107        session.closeDataConnection();
108        sendFinalReply(session);
109
110        afterProcessData(command, session, invocationRecord);
111    }
112
113    /**
114     * Send the final reply. The default implementation sends a reply code of 226 with the
115     * corresponding associated reply text.
116     * @param session - the Session
117     */
118    protected void sendFinalReply(Session session) {
119        sendReply(session, finalReplyCode, finalReplyMessageKey, finalReplyText, null);
120    }
121
122    /**
123     * Perform any necessary logic before transferring data across the data connection.
124     * Do nothing by default. Subclasses should override to validate command parameters and
125     * store information in the InvocationRecord.
126     *
127     * @param command - the Command to be handled
128     * @param session - the session on which the Command was submitted
129     * @param invocationRecord - the InvocationRecord; CommandHandlers are expected to add
130     *      handler-specific data to the InvocationRecord, as appropriate
131     *
132     * @throws Exception
133     */
134    protected void beforeProcessData(Command command, Session session, InvocationRecord invocationRecord) throws Exception {
135        // Do nothing by default
136    }
137
138    /**
139     * Abstract method placeholder for subclass transfer of data across the data connection.
140     * Subclasses must override. The data connection is opened before this method and is
141     * closed after this method completes.
142     *
143     * @param command - the Command to be handled
144     * @param session - the session on which the Command was submitted
145     * @param invocationRecord - the InvocationRecord; CommandHandlers are expected to add
146     *      handler-specific data to the InvocationRecord, as appropriate
147     *
148     * @throws Exception
149     */
150    protected abstract void processData(Command command, Session session, InvocationRecord invocationRecord) throws Exception;
151
152    /**
153     * Perform any necessary logic after transferring data across the data connection.
154     * Do nothing by default.
155     *
156     * @param command - the Command to be handled
157     * @param session - the session on which the Command was submitted
158     * @param invocationRecord - the InvocationRecord; CommandHandlers are expected to add
159     *      handler-specific data to the InvocationRecord, as appropriate
160     * @throws Exception
161     */
162    protected void afterProcessData(Command command, Session session, InvocationRecord invocationRecord) throws Exception {
163       // Do nothing by default
164    }
165
166    /**
167     * Send the preliminary reply for this command on the control connection.
168     *
169     * @param session - the Session
170     */
171    private void sendPreliminaryReply(Session session) {
172        sendReply(session, preliminaryReplyCode, preliminaryReplyMessageKey, preliminaryReplyText, null);
173    }
174
175    /**
176     * Set the completion reply code sent after data transfer
177     * @param finalReplyCode - the final reply code
178     *
179     * @throws AssertFailedException - if the finalReplyCode is invalid
180     */
181    public void setFinalReplyCode(int finalReplyCode) {
182        assertValidReplyCode(finalReplyCode);
183        this.finalReplyCode = finalReplyCode;
184    }
185
186    /**
187     * Set the message key for the completion reply text sent after data transfer
188     * @param finalReplyMessageKey - the final reply message key
189     */
190    public void setFinalReplyMessageKey(String finalReplyMessageKey) {
191        this.finalReplyMessageKey = finalReplyMessageKey;
192    }
193
194    /**
195     * Set the text of the completion reply sent after data transfer
196     * @param finalReplyText - the final reply text
197     */
198    public void setFinalReplyText(String finalReplyText) {
199        this.finalReplyText = finalReplyText;
200    }
201
202    /**
203     * Set the completion reply code sent before data transfer
204     * @param preliminaryReplyCode - the preliminary reply code to set
205     *
206     * @throws AssertFailedException - if the preliminaryReplyCode is invalid
207     */
208    public void setPreliminaryReplyCode(int preliminaryReplyCode) {
209        assertValidReplyCode(preliminaryReplyCode);
210        this.preliminaryReplyCode = preliminaryReplyCode;
211    }
212
213    /**
214     * Set the message key for the completion reply text sent before data transfer
215     * @param preliminaryReplyMessageKey - the preliminary reply message key
216     */
217    public void setPreliminaryReplyMessageKey(String preliminaryReplyMessageKey) {
218        this.preliminaryReplyMessageKey = preliminaryReplyMessageKey;
219    }
220
221    /**
222     * Set the text of the completion reply sent before data transfer
223     * @param preliminaryReplyText - the preliminary reply text
224     */
225    public void setPreliminaryReplyText(String preliminaryReplyText) {
226        this.preliminaryReplyText = preliminaryReplyText;
227    }
228
229}
230